June 2017
Problem of the Month
The Omnipotent Key
by Miko Zhang, Delta High School, Delta, Colorado
Find an omnipotent key (a number) that can open four locks using the following clues:
(1) The first lock is an even number.
(2) The second lock is a number whose factors add up to 42.
(3) The third lock is a multiple of 2 and 5.
(4) The fourth lock is a double digit.
What is the number on the omnipotent key?